The Fed and Apple kept the stock market from pulling back too sharply this week.

The tendency of central banks to do whatever it takes to help the economy is very much in the minds of investors, after the Federal Reserve announced it would buy more mortgage-backed securities to stimulate the economy.

"You can't fight the Fed," said Paul Powers, head of equity trading at Raymond James. "Central banks will keep trying to prop up the market, so investors don't want to sell out."

Even as steel producer Nucor(NUE) and shipping giant FedEx(FDX) cut forecasts Tuesday morning, investors ignored all that and looked more towards the millions of consumers clamoring to buy a new iPhone this Friday.

Apple(AAPL), an outsized component of the S&P 500, has continually reached new all-time highs in the past two weeks. It crossed the $700 mark Tuesday morning and closed above that level.

But uncertainty in Europe abounds, particularly over whether Spain will request a bailout, or even qualify for one. Spain's troubles dampened any enthusiasm investors had over the ECB's recent announcement that it would be willing to buy sovereign debt.

Europe's economy may become increasingly fragmented though. Germans appear to be more optimistic than expected in the face of the continent's issues, according to a report on German investor confidence released Tuesday. Nonetheless, Carsten Brzeski, an economist with ING Bank in London, wrote in a note to clients that the Germany economy may finally be approaching a soft landing.

Oil prices fell for the second day in a row, after plunging more than $3 in less than a minute during Monday's trading session. The U.S. Commodities Futures Trading Commission is reportedly investigating the cause, which left many traders scratching their heads. U.S. crude prices slid another $1.33, or 1.4%, to close at $95.29 a barrel.

The sell-off dragged down major oil stocks, including Marathon Petroleum(MPC) and WPX Energy(WPX), which declined more than 3%.

The euro lost ground against the U.S. dollar, but, at $1.30, still remains at a five-month high. European stocks closed down between 0.4% and 1.2%.

Asian markets remained under pressure as investors worried about U.S. trade relations with China. This week, a territorial dispute heated up over a small group of uninhabited islands claimed by both Japan and China. Asian markets ended lower with the Shanghai Composite dropping 0.9%, the Hang Seng in Hong Kong sliding 0.3% and Japan's Nikkei falling 0.4%.

Another signal on the state of the economy was the Commerce Department's second-quarter data on the nation's current trade deficit, which fell from $133 billion to $117 billion. That was followed by a Treasury Department report that showed foreign investors bought $73.7 billion of U.S. securities in July.

A monthly report on builder confidence from the National Association of Home Builders came in higher than expected at 40, up from 37 last month.

FedEx delivers bad tidings

Companies:Yahoo's(YHOO) stock moved up 1.5% after the company announced that it would return most of the proceeds from selling a portion of its stake in China's Alibaba to shareholders.